详解asp.net core封装layui组件示例分享

前端  /  管理员 发布于 4年前   469

用什么封装？这里只是用了TagHelper，是啥？自己瞅文档去

在学习使用TagHelper的时候，最希望的就是能有个Demo能够让自己作为参考

• 怎么去封装一个组件？
• 不同的情况怎么去实现？
• 有没有更好更高效的方法？

找啊找啊找，最后跑去看了看mvc中的TagHelpers，再好好瞅了瞅TagHelper的文档

勉强折腾了几个组件出来，本来想一个组件一个组件写文章的，但是发现国庆已经结束了~

Demo下载

效果预览

代码仅供参考,有不同的意见也忘不吝赐教

Checkbox复选框组件封装

标签名称：cl-checkbox

标签属性： asp-for:绑定的字段，必须指定

1. asp-items:绑定单选项 类型为：IEnumerable<SelectListItem>
2. asp-skin:layui的皮肤样式，默认or原始
3. asp-title:若只是一个复选框时显示的文字，且未指定items，默认Checkbox的值为true

其中在封装的时候看源代码发现两段非常有用的代码

1.判断是否可以多选：

复制代码 代码如下:

var realModelType = For.ModelExplorer.ModelType; //通过类型判断是否为多选 var _allowMultiple = typeof(string) != realModelType && typeof(IEnumerable).IsAssignableFrom(realModelType);

2.获取模型绑定的列表值(多选的情况)

复制代码 代码如下:

var currentValues = Generator.GetCurrentValues(ViewContext,For.ModelExplorer,expression: For.Name,allowMultiple: true);

这3句代码是在mvc自带的SelectTagHelper中发现的.

因为core其实已经提供了非常多的TagHelper,比如常用的select就是很好的参考对象，封装遇到问题的时候去找找看指不定就又意外的收获.

CheckboxTagHelper代码

using System.Collections.Generic;using Microsoft.AspNetCore.Mvc.Rendering;using Microsoft.AspNetCore.Mvc.ViewFeatures;using Microsoft.AspNetCore.Razor.TagHelpers;namespace LayuiTagHelper.TagHelpers{ /// <summary> /// 复选框 /// </summary> /// <remarks> /// 当Items为空时显示单个，且选择后值为true /// </remarks> [HtmlTargetElement(CheckboxTagName)] public class CheckboxTagHelper : TagHelper {  private const string CheckboxTagName = "cl-checkbox";  private const string ForAttributeName = "asp-for";  private const string ItemsAttributeName = "asp-items";  private const string SkinAttributeName = "asp-skin";  private const string SignleTitleAttributeName = "asp-title";  protected IHtmlGenerator Generator { get; }  public CheckboxTagHelper(IHtmlGenerator generator)  {   Generator = generator;  }  [ViewContext]  public ViewContext ViewContext { get; set; }  [HtmlAttributeName(ForAttributeName)]  public ModelExpression For { get; set; }  [HtmlAttributeName(ItemsAttributeName)]  public IEnumerable<SelectListItem> Items { get; set; }  [HtmlAttributeName(SkinAttributeName)]  public CheckboxSkin Skin { get; set; } = CheckboxSkin.默认;  [HtmlAttributeName(SignleTitleAttributeName)]  public string SignleTitle { get; set; }  public override void Process(TagHelperContext context, TagHelperOutput output)  {   //获取绑定的生成的Name属性   string inputName = ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For?.Name);   string skin = string.Empty;   #region 风格   switch (Skin)   {    case CheckboxSkin.默认:     skin = "";     break;    case CheckboxSkin.原始:     skin = "primary";     break;   }   #endregion   #region 单个复选框   if (Items == null)   {    output.TagName = "input";    output.TagMode = TagMode.SelfClosing;    output.Attributes.Add("type", "checkbox");    output.Attributes.Add("id", inputName);    output.Attributes.Add("name", inputName);    output.Attributes.Add("lay-skin", skin);    output.Attributes.Add("title", SignleTitle);    output.Attributes.Add("value", "true");    if (For?.Model?.ToString().ToLower() == "true")    {     output.Attributes.Add("checked", "checked");    }    return;   }   #endregion   #region 复选框组   var currentValues = Generator.GetCurrentValues(ViewContext,For.ModelExplorer,expression: For.Name,allowMultiple: true);   foreach (var item in Items)   {    var checkbox = new TagBuilder("input");    checkbox.TagRenderMode = TagRenderMode.SelfClosing;    checkbox.Attributes["type"] = "checkbox";    checkbox.Attributes["id"] = inputName;    checkbox.Attributes["name"] = inputName;    checkbox.Attributes["lay-skin"] = skin;    checkbox.Attributes["title"] = item.Text;    checkbox.Attributes["value"] = item.Value;    if (item.Disabled)    {     checkbox.Attributes.Add("disabled", "disabled");    }    if (item.Selected || (currentValues != null && currentValues.Contains(item.Value)))    {     checkbox.Attributes.Add("checked", "checked");    }    output.Content.AppendHtml(checkbox);   }   output.TagName = "";   #endregion  } } public enum CheckboxSkin {  默认,  原始 }}

使用示例

@{string sex="男";var Items=new List<SelectListItem>()   {    new SelectListItem() { Text = "男", Value = "男" },    new SelectListItem() { Text = "女", Value = "女"},    new SelectListItem() { Text = "不详", Value = "不详",Disabled=true }   };}<cl-checkbox asp-items="Model.Items" asp-for="Hobby1" asp-skin="默认"></cl-checkbox><cl-checkbox asp-for="Hobby3" asp-title="单个复选框"></cl-checkbox>

Radio单选框组件封装

标签名称：cl-radio

1. 标签属性： asp-for:绑定的字段，必须指定
2. asp-items:绑定单选项 类型为：IEnumerable<SelectListItem>

太简单了，直接上代码了

RadioTagHelper代码

using System;using System.Collections.Generic;using Microsoft.AspNetCore.Mvc.Rendering;using Microsoft.AspNetCore.Mvc.ViewFeatures;using Microsoft.AspNetCore.Razor.TagHelpers;namespace LayuiTagHelper.TagHelpers{ /// <summary> /// 单选框 /// </summary> [HtmlTargetElement(RadioTagName)] public class RadioTagHelper : TagHelper {  private const string RadioTagName = "cl-radio";  private const string ForAttributeName = "asp-for";  private const string ItemsAttributeName = "asp-items";  [ViewContext]  public ViewContext ViewContext { get; set; }  [HtmlAttributeName(ForAttributeName)]  public ModelExpression For { get; set; }  [HtmlAttributeName(ItemsAttributeName)]  public IEnumerable<SelectListItem> Items { get; set; }  public override void Process(TagHelperContext context, TagHelperOutput output)  {   if (For == null)   {    throw new ArgumentException("必须绑定模型");   }   foreach (var item in Items)   {    var radio = new TagBuilder("input");    radio.TagRenderMode = TagRenderMode.SelfClosing;    radio.Attributes.Add("id", ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For.Name));    radio.Attributes.Add("name", ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For.Name));    radio.Attributes.Add("value", item.Value);    radio.Attributes.Add("title", item.Text);    radio.Attributes.Add("type", "radio");    if (item.Disabled)    {     radio.Attributes.Add("disabled", "disabled");    }    if (item.Selected || item.Value == For.Model?.ToString())    {     radio.Attributes.Add("checked", "checked");    }    output.Content.AppendHtml(radio);   }   output.TagName = "";  } }}

使用示例

@{string sex="男";var Items=new List<SelectListItem>()   {    new SelectListItem() { Text = "男", Value = "男" },    new SelectListItem() { Text = "女", Value = "女"},    new SelectListItem() { Text = "不详", Value = "不详",Disabled=true }   };}<cl-radio asp-items="@Items" asp-for="sex"></cl-radio>

最后再来一个开关组件

单个复选框其实可以直接用开关代替，恰巧layui中也有，于是也将开关单独的封装了一下，代码大同小异

就这个 

使用也简单： <cl-switch asp-for="Hobby4" asp-switch-text="开启|关闭"></cl-switch>


namespace LayuiTagHelper.TagHelpers{ /// <summary> /// 开关 /// </summary> [HtmlTargetElement(SwitchTagName)] public class SwitchTagHelper : TagHelper {  private const string SwitchTagName = "cl-switch";  private const string ForAttributeName = "asp-for";  private const string SwitchTextAttributeName = "asp-switch-text";  protected IHtmlGenerator Generator { get; }  public SwitchTagHelper(IHtmlGenerator generator)  {   Generator = generator;  }  [ViewContext]  public ViewContext ViewContext { get; set; }  [HtmlAttributeName(ForAttributeName)]  public ModelExpression For { get; set; }  [HtmlAttributeName(SwitchTextAttributeName)]  public string SwitchText { get; set; } = "ON|OFF";  public override void Process(TagHelperContext context, TagHelperOutput output)  {   string inputName = ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For?.Name);   output.TagName = "input";   output.TagMode = TagMode.SelfClosing;   if (For?.Model?.ToString().ToLower() == "true")   {    output.Attributes.Add("checked", "checked");   }   output.Attributes.Add("type", "checkbox");   output.Attributes.Add("id", inputName);   output.Attributes.Add("name", inputName);   output.Attributes.Add("value", "true");   output.Attributes.Add("lay-skin", "switch");   output.Attributes.Add("lay-text", SwitchText);  } }}

总结

封装的还很粗糙，正常的使用是没问题的，若发现问题，还望指出。

因为layui是直接在页面加载后渲染的表单标签，故没有多少和layui相关的样式。

除了一些表单组件之外，其实还对选项卡，时间轴，分页，代码显示组件做了一些封装，这些后面再介绍了。

当然，有兴趣的朋友可以先去一睹为快看看都实现了哪些组件

仓库地址

WeDemo分支clone命令:git clone https://git.coding.net/yimocoding/WeDemo.git -b LayuiTagHelper

选项卡，时间轴，分页，代码显示等Demo打包下载

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。